Good post, and I totally agree. Maybe semantics, but I wouldn't call that a messed up trigger press in your video. That's a timing error (almost a pre-ignition push), and in my experience only really good shooters can recognize and stop that as it's happening (as you did).
I do agree about the tradeoff between gripping hard and keeping the trigger finger and other fingers from co-contracting. I focus on my wrist, and that seems to help. "Seems" is the operative word because every time I think I've really got my WHO shooting squared away, some issue crops up for whack-a-mole.